Cimetidine and coumarin therapy of melanoma.

mentioned extracerebral sources, especially under the heavy strain of a marathon race, seem to us a more probable source for CK-BB activity in marathon runners after a race. This also tallies with the observation of Phillips et al. that none of the runners demonstrated any neurological abnormalities after the race. Furthermore, most of the runners also revealed increased heart-type isoenzyme (CK-MB) activities and crossreactivity of CK-MB in radioimmunoassays cannot be excluded as a possible explanation for the observations made by Phillips et al., as they note. We however, are, more concerned about the occurrence of increased serum CK-MB in most marathon runners after a race.